Combined overturn and ignition switch



Oct. 14, 1941. J. F. COURTNEY COMBINED OVERTURN AND IGNITION SWITCH Filed Feb. 21, 1941 3 Sheet -Sheet l Oct; 14, 1941. F, COURTNEY 2,258,846

"COMBINED OVERTURN AND IGNITION SWITCH Filed Feb. 21, 1941 5 Sheets-Sheet 2 Patented o... 14. "1941 COMBINED OVERTUBN AND IGNITION" SWITCH 1 Joseph F. Courtney, Chicago, 111.

Application February 21, 1941, Serial No. 379,938 17 Claims. (01. 200-44) The present invention relates to combined overturn and ignition switches and is particularly concerned with switches adapted to be used to control the ignition circuits of automotive vehicles and to permit their make or break manually or their break automatically when the automotive vehicle is overturned in any direction.

One of the objects of the invention is the provision of an improved ignition switch which is simple and capable of being used for a long life without necessity for repair, and which is also adapted to serve as an overturn switch cutting out the electrical-circuit when the vehicle is over-' turned accidentally or otherwise.

Another object of the invention-is the provision of an improved overturn and ignition switch for automotive vehicles which is adapted to be actuated by a key-controlled tumbler barrel.

Another object of the invention is the provision of an improved ignition and overturn switch of the type utilizing a mercury switch unit in which provision is made for preventing the breaking of the circuit due to surges of the mercury when the vehicle turns a corner, stops suddenly, or otherwise changes its rate of motion suddenly.

Another object of the invention is the provision of a combined overturn and ignition switch of the mercury type for automotive vehicles which is so constructed that there is a minimum amount of contact resistance produced in the elements of the switch and in which the movable parts are constantly kept bright and in a good contacting condition.

Another object of the invention is the provision of a switch of the class described which is com pact, capable of economical manufacture, which has a minimum number of parts, and which may be manufactured at a'very low cost so that it may be placed within the range of a larger number of purchasers.

will be apparent from the following description and the accompanying drawings, in which similar characters of reference indicate similar parts of the line' 3-3 of Fig. 2 looking in the direction or the arrows;

Fig. 4 is a transverse sectional view taken on theplane of the line i- -fl of Fig. 2 looking in the direction of the arrows;

Fig. 5 is a transverse sectional view taken on the plane of the line 5-5 of Fig. 2 looking in the direction of the arrows;

Fig. 6 is a transverse sectional view taken on the plane of the line 6-6 of Fig. 2 looking in the direction of the arrows;

Fig. 7 is an enlarged fragmentary sectional view of the connector end of a switch embodying theinvention, taken on the plane of the line -1 of Fig. 6 looking in the direction of the arrows Fig. 8 is a fragmentary sectional view of the structure at the opposite end of the housing Another object of the invention is the provision of an improved and simplified turnover switch structure which may be used separate and apart from any ignition switch, and which is adapted to cut oil the electric current in any of the circuits of an automotive vehicle when the vehicle is overturned in a direction.

Another object of the invention is the provision of an improved overturn switch which is eflicient and dependable, and capable of such economical manufacture that it may be placed within the range of a large number of purchasers and used for standard equipment on automotive vehicles by the manufacturers of such vehicles.

Other objects and advantages of the invention taken on the plane of the line 8-8 of Fig. 3 looking in the direction of the arrows;

Fig. 9 is a sectional view taken through the mercury switch unit on a plane passing through the axis of the unit, that is, the plane of the line 9-9 of Fig. 2 looking in the direction of the arrows, with the switch unit in closed position; and

Fig. 10 is a similar view of the mercury switch unit, with the parts in the position which they assume when the circuit has been opened by means of the key.

Fig. 11 is a front elevational view ofa modification embodying a simple overturn switch installed on the dash or some other vertical part of an automotive vehicle;

Fig. 12 is a fragmentary vertical sectional view,

taken through the dash, with aside elevational view of the overturn switch of Fig. 11, looking in the direction of the arrows;

plane of the line "-44 of Fig. 13, looking in. the direction of the arrows;

Fig. is a sectional view, taken on the plane of the line 15-15 of Fig. 14, looking in the direction of the arrows.

Referring to Fig. l, indicates the sheet metal dash of an automotive vehicle which is provided with an aperture 2| for receiving the threaded tumbler barrel housing 22 which is usually provided with a knurled finishing ring on its front end. The tumbler barrel housing is secured to the dash 20 by means of a thin hexagonal nut 24 mounted on the threaded portion and driven into such position that it clamps the dash 20 between the nut 24 and the annular flange or ring 23 which is also threaded on the barrel 22 as shown in Fig, 2.

The tumbler barrel housing 22 comprises a cylindrical metal member having its external surface threaded, and it rotatably supports the usual tumbler barrel 25, such as a tumbler barrel of the Yale type which cannot be rotated until the proper key 26 is inserted in its keyhole, thereby moving all of its tumblers to such a position that they are withdrawn from internal slots of the tumbler barrel housing 22. The key 26 is thus adapted to rotate the tumbler barrel and with it the key plate 21 (Fig. 2) which is mounted on the inner end of the tumbler barrel and which is provided with a pair of longitudinally extending driving ears 28 for engaging the switch mechanism.

The tumbler barrel housing 22 may fixedly support a switch housing 29 comprising a cylindrical sheet metal cup which fits on a radially extending flange 38 carried by the tumbler barrel housing and which has an inwardly extending annular flange 3| engaging the flange 30 and abutting an annular'shoulder 32. These two parts may be secured together by soldering, welding, spinning, or by close frictional fit, so that the housing 29 is fixedly secured to the tumbler barrel housing 22.

At its opposite end, the switch housing 29 is provided with a pair of longitudinally projecting integral cars 33 (Fig. 6) which are adapted to engage in the radial slots 34 formed in a fiber plate 35 which forms a closure for the end of the cylindrical housing 29. The fiber plate 35 may be constructed of indurated insulating fiber or a fiber comprising fabric impregnated with a phenolic condensation compound, and it is preferably circular so that its outer edge is flush with the surface of the switch housing 29 except at the slots 34 in which the cars 33 are received. The ears 33 are bent over, as shown in Fig. '7, to retain the fiber plate 35 against the end of the housing 29.

The insulating plate 35 is adapted to provide a support for a pair of connectors 36 and 31 which may be identical in structure but which are preferably oppositely disposed to separate the wires, which are connected to the conductors, as far as possible. For example,connector 36 comprises a sheet metal member having a flat attaching flange 38 of rectangular shape, in plan, the at: taching flange having a pair of supporting cars 39 (Fig. '7, Fig. 2) and the ears 39 being bent at right angles to the attaching flange 38.

The ears39 pass through slots 40 and 41 (Fig 2) in the insulatingplate 35 and they are bent over inside the switch housing 29 to secure two other metal members 42 and 43 to the same insulating plate. For example, each of these metal members 42, 43 may have attaching flanges 44 or 45 (Fig. 7) which are provided with inwardly extending slots 46, 41 (Fig. 6) for receiving the ears 39.

Thus, when the cars 39 are bent over toward each other, as shown in Fig. 6, the metal member 43 is fixedly secured to the insulating plate 35 against rotative or other movement. Further reference will be made to these metal members 42 and 43 in the further description of the electric switch.

The connectors 36 and 31 have their attaching flanges 38 provided with a connector flange 46 (Fig. '1) extending at right angles to the attachment flange 38 and provided with a threaded bore 49 for receiving a screw bolt 58.

The connector flange is preferably formed with one or more wire guiding ears 5|, 52 (Fig. 3) bent at right angles to the connector flange 48 and adapted to hold a conductor wire 53 under the 00 head of the bolt as it is driven home into clamping relation with the wire 53 and connector flange 48. Thus the connectors 38 and 31 serve to provide means for connecting the ignition and overturn switch in the electrical circuit.

The switch mechanism is preferably all supported on the insulating plate 35 and for this purpose the two metal members 42 and 43 are provided and secured as previously described. Metal member 42 comprises a sheet metal strap having the attaching flange 44 and an elongated main body 54 which extends at right angles to the insulating plate 35.

At 55 this strap is bent at an angle of forty-five degrees to extend diagonally by means of the portion 56 and it is again bent forty-five degrees at 51 so that its end portion 58 extends parallel to the insulating plate 35 and is adapted to provide a bearing for supporting one end oi. a rotatable mercury switch unit. For this purpose the end portion 58 is formed with a bearing aperture 59. The metal member 43 serves as a bearing member for the other end of the rotatable mercury switch unit, and in addition to its attaching flange 45, it has a diagonally extending ofiset portion 60 (Fig. 7) and a bearing portion 6| extending parallel to the insulating plate 35.-

This bearing portion 6| again has a bearing aperture 62 which is axially aligned with the bearing aperture 59 Just described in the member 42. The bearings 59 and 62 rotatably support a mercury switch unit 63 (Fig. 3), the structure of which is shown in Figs. 9 and 10.

This mercury switch unit comprises a centrally located partition 64 of porcelain or other suitable refractory having electrical insulating properies. This ceramic partition 64 is surrounded by a toroidal bead of glass 65, and the partition supports a pair ofsheet metal cup-shaped members 66 and 61 of similar shape adapted to act as terminals for the mercury switch and as parts of the housing for the switch.

The cup-shaped terminal members 66 and 61 hermetically sealed container 63 for receiving a I predetermined amount of mercury 10. The ceramic partition or barrier 64 is formed with ,underthe depending edges 66B 01' the glass head to fasten these parts permanently together.

The amount of mercury 18 in the mercury switch 63 is suflicient so that it fills the lower part of each chamber 12, 13 located on the opposite sides of the partition 64 and extends through the aperture H' to establish an electrical connectionbetween the terminal members 66 and '61 when'the mercury switch is in the position of Fig. 9.

When it is wholly inverted, however, from the position of Fig. 9, the aperture 1I would be located too high to permit connection being established between the pools of mercury in the chambers 12 and 13. Furthermore, when the mercury switch unit 63 is tilted laterally, as shown in Fig. 10, the mercury runs into one of the cupshaped members 61, and the circuit is broken between the terminal members 66 and 61 as shown in Fig. 10.

In order to prevent the surging of the mercury 18 in the chambers 12 and 13 upon sudden movements or braking efforts or action of centrifugal force on the motor-vehicle, the terminal members 66 and 61 are each preferably provided with a baffle 14, 15. The baflies 14 and 15 are identical in construction and may consist of an attaching flange 16 which is provided with an aperture at 11 for receiving the inwardly extending protuberance 18 of each terminal 66 or 61.

At its lower end, each attaching flange I6 is provided with a laterally turned balile flange 19 which extends substantially across the chamber 12 or 13 above the mercury 18, but has a slight space or opening at 88, 8i at each end of the baiiie flange 19. There is also a slot provided in the baffle flange 19 midway between its ends at 82.

Each of the metal cups 66, 61 is preferably provided on its inside, below the baflies 14, 15, and on the flat side of the wall, with a contact member I I8, I I8 of non-corrodible metal adapted to be w'et by the mercury at all times, such as, for example, a thin rectangular strip of plati-. num. These contact members H8, H9 may be soldered to the inner walls of the cup, below the free surface of the mercury, so that, although the steel cups 66, 61 may become corroded, the platinum contacts H8, 9 will always produce an effective contact of low resistance with the mercury body. The amount of mercury and the location of the contacts is preferably such that the circuit is broken at the partition 64, as shown in Fig. 10, between two bodies of mercury.

The location of the bailie flange 19 with respect to the mercury is such that the meniscus of the mercury is slightly flattened so that the baffle tends to flatten out the mercurial meniscus and to hold it down against surges. The rest of the space in the chambers 12 and 13 is filled with an inert gas and when the mercury switch is tilted, the mercury runs through the slot 82, the gas running in at the cracks 88 and 8| at each end of the baille flange 19.

The mercury switch unit 63 is fixedly secured to a pair of pintle arms 83 and 84 (Fig. 3). These pintle arms may be identical in construcmembers 86 and 61, and extend in opposite directions, with their pintle flanges extending over toward the axis 01' the mercury switch unit. In this case the axis of the switch unit is a diametrical line extending through the partition 64 midway between its sides because the mercury switch 63 is not mounted for rotation upon the geometrical axis of generation 01' the cups 66 and 61.

Each of these pintle arms 83 or 84 comprises 'an elongated sheet metal strap, the inner end of which has a circular body portion 85 formedwith a partially spherical depression 86, the opposlte side of which provides a protuberance 81 which fits in the spherical depression 86 formed in either terminal member 66 or 61.

This body portion is then fixedly secured to the terminal 68 or 61 by welding the body 85 to terminal or 81 at the spherical depression 86 or by soldering or brazing or other convenient fastening means.

Each pintle arm 83 or 84 has a strap-like portion extending radially from the body 85 and provided with a laterally turned pintle flange 88 or 88 extending at right angles to the strap 84 or 83. Pintle flanges 88 and 89 also have apertures 98 and M which are axially aligned with each other and the pintle flanges 88 and 89 are parallel. to each other and spaced from each other sufllciently so that they fit between the bearing flanges 6| and 68 of the supporting members 42 and 43.

The pintles of each of these bearings may consist of a tubular rivet 82, 93. The tubular rivet 92 extends through the supporting member 43 and through the aperture 9| of the pintle arm 83 and also through a spring washer 94. The tubular rivet is riveted over at each end by means of the spring washer. The flanges 6| and 89 are resiliently pressed together but rotation is permitted between these flanges.

At the tubular rivet 93 the arrangement is exactly the same except this rivet is longer and it also passes through an, insulating fiber plate 96 of the same material as the plate 35. This plate is circular but smaller in size so that it may be housed inside the housing 29 and it is provided with a pair of oppositely located radial slots 96, 81 (Fig. 4), the slots preferably being of rectangular cross-section.

The insulating plate is arranged to rotate with the mercury switch 63 and for this purpose the pintle flange 88 is provided with an integral extension 98 (Fig. 4) which is in the form of an ear that is bent outward at right angles in the slot 99 of the insulating plate 95 and bent backward on itself at I88 to clamp the plate 96. Thus the plate 95 is fixedly secured to the member 84 and it must rotate with the switch 63 and members 89 and 84. a

The length of the mercury unit assembly, including the members carried by insulating plate 35 in Fig. 3, is such in relation to the length of the housing 29, that the insulating plate 95 is brought into the position shown in Fig. 2 when the insulating plate 35 fits on the end of the housing 29. That is, the insulating plate 95 then has within its slots 96 and 91 the axially extending ears 28 of the rotatably mounted member 21 that is actuated by the tumbler barrel.

This member 21 is fixed to the tumbler barrel by means of a pair of riveted integral lugs I8I located in apertures I82 (Fig. 8). Another insulating fiber disk I83 is interposed between the tion, but are secured to the opposite terminal 75 plate 21 and the end 01 the rivet 93 and is held in place by means of radial slots I04 which also receive the ears 28 (Fig. 8). l

This plate I03 insulates the rivet and clamping ear I 'from the tumbler barrel.

As seen in Fig. 5, the metal plate 21 actuated by the tun'ibler barrel and having the axially projecting ears 28, is a metal disk provided with radially extending lugs I05, I05. A pair of metal pins I01 and I08 is carried by the end flange 30 of the tumbler barrel housing 22 and these pins engage the stop surfaces I09, IIO, on the lugs I05, I06, and prevent the rotation of the tumbler barrel and the switch mechanism beyond a predetermined range of movement.

When the tumbler barrel is in the position of Fig. 8 and the mercury switch is in the position of Fig. 8 or Fig. 9, the ignition circuit is turned on. When the key is turned toward the left from the dotted line position of Fig. to the full line position of Fig. 5, the mercury switch moves from the position of Fig. 9 to that of Fig. 10 and the circuit is broken.

No matter whether the mercury switch is open or closed depending on the tumbler barrel, the circuit will be broken when the vehicle is overturned, because this would make the mercury switch assume a position inverted from either that of Fig. 9 or Fig. 10, and there is only one horizontal position, that of Fig. 9, for the vehicle in which the ignition circuit can be closed.

Thus, the overturn switch is adapted to assure the safety of the vehicle against possibility of burning due to closed ignition or other circuits when the vehicle is overturned.

The ignition switch may be used as a. master switch for controlling all of the circuits of the vehicle, if desired, to make sure that all circuits are turned off when the vehicle is overturned.

The present switch has a minimum amount of contact resistance because the ,two supporting arms 83, 84 are in constant rubbing contact with the supporting members 42, 43. This resilient rubbing contact is assured by the spring washers 94 on the tubular rivets 92 and 93 and there is no possibility of any loose electrical connections which might cause sparking.

It will thus be observed that I have invented an improved overturn and ignition switch which accomplishes the double function of permitting the ignition to be turned off or on manually and of effecting an opening of the circuit when the vehicle is overturned irrespective of the direction in which it is overturned or of the position of the switch at the time of overturning.

The present ignition switch may be manufactured at a very low cost, yet it is absolutely safe and very compact and dependable in its operation.

Referring to Figs. 11 to 15, these views show a modification embodying a simple overturn switch without any controlling key and tumbler barrel, such as is utilized in Figs. 1 .to 10.

The mercury switch unit 63 utilized in this embodiment may be exactly the same as that previously described. It is disposed with the proper side, marked by the groove I20 upward, so that the eccentrically located aperture H of the partition 54 is located lowermost, as shown in Fig. 9. The bailles 14, 15 are located on top of the mercury 10, whenthe unit is in the position of Fig. 9.

This unit is preferably supported by a pair of sheet metal arms I2I, I22, which may be identical in structure, but reversed in location. Each sheet metal arm has an attaching flange I23, and the attaching flanges are provided with grooves I24, I25 (Fig. 15) on each side for receiving the tongues I28, I21 01 the spring clips I28, I28. Each of the arms I2I, I22 is formed with a partially spherical stamped depression I30 (Fig. 14) which fits in the spherical recess 03 of the mercury switch unit 63. and each of the arms I2I may be secured to one of the metal cups 8B or 61 in the position shown in Figs. 13, 14 by soldering, brazing, or welding, as indicated at I3I, around both sides of that part of each arm I2I, I22 which is adjacent to the wall of the cup 00 or 51.

Each of the arms I2I, I22 preferably is bent laterally at I32 for the purpose of permitting the attachment flanges I23 to be turned inwardly and still spaced from each other. The attachment flanges I23 are at right angles to the main body of each arm I2I, I22, and they have their outer surfaces brought into the same plane for engagement with a flber insulating plate I33, upon which the arms are supported.

The fiber insulating plate I33 is of sufficient size so that in a truly rectangular box it may engage the sides thereof, but in a box with the corners rounded, as shown, it is of sufilcient size to maintain its position by friction and by the fact that any lateral movement would cause this fiber plate to ride upward on the rounded inner portions I34 of the box.

The fiber plate I33 has two pairs of apertures I35, rectangular in shape, and located to receive the upwardly extending arms I35 of the two clips I28, I29.

The clips I28, I29 are preferably carried by electrical connectors I31, I38, and may form integral parts of the attaching flanges I33 of these connectors. The attaching flanges of the connectors may be substantially rectangular metal straps, which are bent at right angles to the connector flanges I40 and which have the upwardly extending lugs I35, I38 carried by the opposite sides of each attachment flange.

The lugs I35, I36 are long enough to extend through an outer flber plate I, which is also provided with the registering apertures I 42 and also through the side wall of the housing I43, the fiber plate I33, and about the attachment flanges I23 of the supporting arms I2I, I22,

The ends of these fingers or legs I35, I 35 are indicated at I25, I21 in Fig. 15, where they are bent over towards each other to secure the connectors I31, I38 and the arms I2I, I22 to the fiber plates I33, I, and to the housing I43.

The electrical connectors I31, I38 have their connector flanges I40 each provided with a threaded bore I44 for receiving a screw bolt I45,

" the head of which is adapted to clamp an electrical conductor I46 to the connector flange I40.

The connector flange I40 may also have a pair of outwardly extending lugs I41, I48 oppositely located and adapted to confine the conductor I46 under the head of the screw bolt I45, as the bolt is driven home to eilect a more secure connecion.

The fiber plates I33, I 4| may be of indurated fiber impregnated with a phenolic condensation compound or any fiber reinforcing compound.

The outer fiber plate I may be smaller in area and only of suflicient size to cover the aperture I49 in the side wall I50 of the housing. The housing I43 may comprise a stamped sheet metal box which has the four side walls I 50, I 5I, I52, I53 and an end wall I54. These walls are preferably joined by the rounded portions I55 so as to permit the formation of the box by a stamp- I 2,258,846 ing or drawing operation and to eliminate sharp unit may be placed on the front or the back of the dash, and in Fig. 12 it is disposed on the rear of the dash, with the heads of the screw bolts I51 appearing on the front. Electrical connections to the overturn switch are accomplished by connecting appropriate conductors I46 to the connectors I31, I38, and the switch should be included in series with'the ignition circuit that includes the ignition switch.

In most cases it may be connected between the ammeter and the ignition switch in the conventional circuit, although in some automotive vehicles it is necessary to connect it between the ignition switch and ignition coil or between the ammeter and ignition coils. The proper place to connect such a switch so as to disable the igni-' tion and other circuits, when the vehicle overturns, will be apparent to one skilled in the art, from the wiring diagram of the vehicle.

The operation of this overturn switch is substantially the same as that described with respect to th device of Figs. 1 to 10, except that for its rotative support, whereby the necessity for flexible conductors leading to the mercuryswitch unit is eliminated, and connector means carried by said support for slidably and rotatably engaging parts carried by said terminals.

,2. A combined ignition and overturn switch comprising a support, a mercury switch unit rotatably mounted on said support and comprising a housing having a predetermined quantity of mercury therein, and a key actuated tumbler.

barrel for controlling the rotation of said mercury switch unit, said mercury'switch being of the type having one rotative position in which its circuit is closed and its circuit being open in the other rotative positions of said switch.

3. In a combined overturn and ignition switch, the combination of a tumbler barrel housing with a tumbler barrel rotatably mounted in said housing and controlled by a key, a switch supporting frame carried bysaid tumbler barrel housing and extending axially therefrom, and a the present unit is supported in fixed relation to the parts of the automotive vehicle.

Surges of the mercury, which might otherwise disconnect the circuit, are prevented by the baffles I4, 15; but when the vehicle is overturned in any direction laterally, or end over end, the circuit is broken, and remains broken until the vehicle is again righted.

Thus, fires will be prevented, which might otherwise be caused by the leaking gasoline and the connected electrical circuit.

The present device may be manufactured very cheaply, as most of its parts are made of sheet metal stampings, and it may be made so cheaply that it is adapted to be used as an article of standard equipment on automotive vehicles sold by the manufacturers of such vehicles.

So far as I am aware, up to the present time figure that it presented any possibility of being used as standard equipment.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction setforth, but desire to avail myself of all changes within the scope of the appended claims. I

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

'1. A combined ignition and overturn switch comprising a support, a mercury switch unit rotatably mounted on said support and comprising a housing having a predetermined quantity of mercury therein, and a key actuated tumbler barrel for controlling the rotation of said mercury switch unit, said mercury switch unit having its electrical terminals arranged to provide mercury switch assembly carried by an insulating member. and adapted to be brought into actuating position with respect to said tumbler barrel when said insulating member is secured to said frame.

4. In a combined overturn and ignition switch,

the combination of a tumbler barrel housing with a tumbler barrel rotatably mounted in said housing and controlled by a key, a switch supporting frame carried by said tumbler barrel housing and extending axially therefrom, and a mercury switch assembly carried by an insulating membar and adapted to be brought into actuating position with respect to said tumbler barrel when said insulating member is secured to said frame, said mercury switch assembly comprising an insulating plate, a pair of aligned bearing arms carried by said plate, a mercury switch, and a pair-of electrical conductors carried by the terminals of said switch and rotatably mounted on said arms.

5. A combined ignition and overturn switch comprising a support, a mercury switch unit rotatably mounted on said support and comprising a housing having a predetermined quantity of mercury therein, and a key actuated tumbler barrel for controlling the rotation of said mercury switch unit, said mercury switch unit being provided on its interior with bafile means engaging the meniscus of the mercury when the switch is in closed position and tending to prevent surges of the mercury which might produce an open circuit upon quick change of position of a vehicle carrying the switch.

6. A mercury switch assembly comprising an insulating plate. a pair of electrical connectors carried by said. insulating plate and secured thereto by integral metal ears passing through said plate, and a mercury switch unit rotatably mounted on'said plate and comprising a hermetic'ally sealed housing including terminals and having a predetermined quantity of mercury in said housing. g

7. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate and secured I thereto by integral metal ears passing through 'and provided with an eccentricallir located aperture.

8. A mercury switch assembly comprising an insulating plate, a pair or electrical connectors carried by said insulating plate and secured thereto by integral metal ears passing through said plate, and a mercury switch unit rotatably mounted on said plate and comprising a herm'etically sealed housing including terminals and having a predetermined quantity of mercury in said housing, said terminals having fixedly secured thereto a pair of oppositely extending pintle arms and bearing arms carried by the ears of said connectors and having rotatable engagement with the pintle arms.

9. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate and secured thereto by integral metal ears passing through said plate, and a mercury switch unit rotatably mounted on said plate and comprising a hermetically sealed housing including terminals and having a predetermined quantity of mercury in said housing, said terminals having fixedly secured thereto a pair of oppositely extending pintle arms and bearing arms carried by the ears of said connectors and having rotatable engagement with the pintle arms, said bearing arms and pintle arms being connected by a pair 01' tubular rivets.

10. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate and secured thereto by integral metal ears passing through assaeae carried by said insulating plate, each connector having securing ears passing through said plate, a pair of bearing arms, one having its bearing located close to said plate and the other having its bearing located in spaced relation to said plate, said bearing arms being secured to said plate by said ears, and a rotatable mercury switch rotatably mounted on said bearing arms. said mercury switch including a housing comprising a pair of metal cups, each,cup being insulated from th other and forming a terminal, and mercury in said housing and connecting said cups when they are in a predetermined rotativ position, each of said cups having secured thereto a pintle arm and said pintle arms extending into rotative engagement with said bearing arms.

14. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate, each connector said plate, and a mercury switch unit rotatably mounted on said plate and comprising a hermetically sealed housing including terminals and having a predetermined quantity of mercury in said housing, said terminals having fixedly secured thereto a pair of oppositely extending pintle arms and bearing arms carried by the .ears of said connectors and having rotatable engagement with the pintle arms, said bearing arms and pintle arms being connected by a pair of tubular rivets, and resilient means causing each bearing arm to slidably engage its pintle arms to effect a continuous bright electrical contact between the pintle arms and bearing arms.

11. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate, each connector having securing ears passing through said plate, a pair 01' bearing arms, one having its bearing located close to said plate and the other having its bearing locatedin spaced relation to said plate, said bearing arms being secured to said plate by said ears, and a rotatable mercury switch rotatably mounted on said bearing .arms.

12. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate, each connector having securing ears passing through said plate, a pair of bearing arms, one having its bearing located close to said plate and the other having its bearing located in spaced relation to said plate, said bearing arms being secured to said plate by said ears, and a rotatable mercury switch rotatably mounted on said bearing arms, said mercury switch including a housing comprising a pair of metal cups, each cup being insulated from the other and iorming a terminal, and,

mercury in said housing and connecting said cups when they are inaipre e te r mined rotative position.

13. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors having securing ears passing through said plate, a pair of bearing arms, one having its bearing located close to said plate and the other having its bearing located in spaced relation to said plate, said bearing arms being secured to said plate by said ears, and a rotatable mercury switch rotatably mounted on said bearing arms, said,

the mercury switch.

15. A mercury switch assembly comprising an insulating plate, a pair of electrical connectors carried by said insulating plate, each connector having securing ears passing through said plate, a pair of bearing arms, one having its bearing located close to said plate and the other having its bearing located in spaced relation to said plate, said bearing arms being secured to said plate by said ears, and a rotatable mercury switch rotatably mounted on said bearing arms, said mercury switch including a housing comprising a pair of metal cups, each cup being insulated from the other and forming a terminal, and mercury in said housing and connecting said cups when they are in a predetermined rotative position, each of said cups having secured thereto a pintle arm and said pintle arms extending into rotative engagement with said bearing arms, and an insulating member fixedly secured to one of said pintle arms and adapted to be used to rotate the mercury switch, and a key-actuated tumbler barrel for rotating said latter insulating member.

16. An overturn switch comprising a supporting housing provided with electrical connectors supsaid connectors carrying metal electrically conducting arms, and a mercury switch unit comprising a pair of sheet metal cups supported in spaced relation to each other by an insulating partition having an aperture extending through 5 said partition and a body of mercury located in said cups and extending through said aperture to efiect a connection when the overturn switch is in upright position, said metal cups each supporting a baflle and adapted to depress the meniscus of the mercury and prevent surges of the mercury which might otherwise break the circuit due to quick movements of the vehicle which supports the switch.

JOSEPH F. COURTNEY, 

